Grounding a mounting hole is usually a good thing. Stray standoffs grounding other stuff is a problem

Sphere478 wrote on 2022-11-15, 16:39:

Grounding a mounting hole is usually a good thing. Stray standoffs grounding other stuff is a problem

I think I did that correctly. The case has only 3 standoff locations. I used screws with nylon washers on those three spots. The rest of the spots use plastic spacers that slot into the grooves in the bottom of the case. It seems to work just fine as far as I can tell. The machine is working, I'm just thinking I don't have it configured for the best performance.

Okay. Another strange question. This is not something I have had an issue with before, so I am curious if there is a fix. I am using an Aztech Sound Galaxy Pro 16 sound card in this 386, and I have noticed with certain games, that they reset the mixer to basically nothing. I have tried different settings with games, such as using Sound Blaster instead of Sound Blaster Pro, or General midi as I have midi card, but the result is always the same. Main volume is set to 33 of 65, Voice is set to 10 of 33, Line in and CD in are set to 0, Mic is set to 33, for whatever reason, and PC Speaker is set to 33. This is a recurring issue with later sierra games, such as Gabriel Knight: Sins of the Fathers, Space Quest 6 (I know, way too much for this machine), Quest for Glory 4 CD, King's Quest 6, and of course Might and Magic III, IV, and V. I know that Might and Magic III does weird things to the mixer, but I haven't had an issue with IV and V on anything prior. They even ask if you want it to modify the mixer, and I answer no. I am guessing it's some sort of configuration issue with how I have this machine set up, but more than that I don't know. Just thought I would ask here, as everyone here is so knowledgeable. I usually just use Sound Blaster cards, but this Aztech card works so well with older games, Sound Blaster mode works in Quest for Glory 2 and Space Quest 3. And that's something that occasionally gives me trouble on a real Sound Blaster Pro 2 card. Probably because I have the SBP2 configured it IRQ 5. Also I have tried changing to the Windows Sound System for Digital audio, but I get a constant crackling and clipping. I checked the volume on the Voice and it's still set to what I have the SBP set to which is 25 of 33.

By the way. It turns out that I also have this board

I’ll be soon upgrading it with a 486 sxl2-66 on interposer.

Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!

In the meantime I have added 20mb of ram and a fasmath black top 40mhz

A cirrus logic 5034 is on its way.

I’m going all out on this build.

For now I am using a cf on a 8-bit isa st-ide eventually when it goes in a case I think it will get a scsi card and a nice 15k rpm scsi drive hehe

Unless opposed I can document the build here, and we can compare notes 😀

My next purchase will probably be ram.

Any thoughts as to the max ram capacity of this board? 128mb? 64 mb? 32mb?

Today I got some 16mb sticks in the mail. 4 of them

They unfortunately don’t seem to be supported.

I got parity ones. Could that be it? Or are they simply just not supported?

4mb x 8 it is then?

System BIOS shadow & Video BIOS shadow = turn on for fastest access

Memory read/write wait stats = as low as possible (you may have to test and retest until you find the system to still be stable)

ISA clock = *most* later cards will tolerate 10MHz fine, but again you may have to experiment - you'll get increased video speed and hard drive transfer from faster ISA clock. You might actually be able to set it faster than that.

Adapter shadow regions = leave off unless you actually have any additional adapters with roms on them

The non-cacheable block/region settings are to do with how the motherboard cache handles caching of various areas in memory - normally you wouldn't cache the rom areas (ie 640kb-1024kb), for example. I'd leave it as-is for now.

Also, regarding the Cirrus card - although it was nothing special in the day for business/windows use, you'll probably find that it's actually pretty good; Cirrus cards are usually pretty solid in terms of memory throughput, which is what DOS games are all about. I've got a mixture of Tseng Labs, Trident and Cirrus cards in various ISA based machines, and the CL-5428 is the fastest of them all, followed closely by the ET4000. The 5426 isn't that far behind the 5428 in terms of technology, so I would expect it to be a good performer.

So is there not really a consensus on the fastest isa card?

I’ve seen the tseng et4000 come up a few times.

I was wanting to get the fastest. Or one that does the best 3d if none of the others do. For this system. Might use it for some light windows games. Though it’ll be a stretch. Kinda a pushing the limits kinda deal.

Anyone able to offer suggestions or insight on the ram thing?

Someone said they think that this ram is for mac only?

Cirrus Logic and Tseng Labs cards seem to trade blows. ET4000 cards tends to be more expensive because the have a reputation as 'the fastest' but in reality that was early on, later cards caught up and are often cheaper.

Dos performance doesn't take any advantage of advanced card/chipset features, so high end windows performance has no bearing on it whatsoever.

For fastest video you will need to design and build CPU-VLB interposer ;P

rasz_pl wrote on 2023-01-07, 18:51:

For fastest video you will need to design and build CPU-VLB interposer ;P

Think that would actually work? Surely there are other things not present on chipset?

Re: Diy VL bus

Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!

My mobo is ready to for some sxl2 overclocking!

Just got the AnyClk device installed! Pretty nifty little device! First test was at 40mhz on a AMD 386dx-40 (soldered on one) next was at 50mhz cpu /100mhz crystal clock. So far stable! More mhz to come!

Edit: tried 5.33x multi. No dice. (106.7fsb) so my max mhz on this cpu lies somewhere between 100 and 106.7 crystal clock.

I have the crystals to find out exactly where, in steps that are actually often less than 1mhz at a time. 😮

So when I get the sxl2 I’m really gonna know what its max clock is for sure 🤣.

I haven’t messed with isa clock ratio. Might try that next. Could be the limiting factor. Also I have some purple ram coming 4mb x 8 (32mb) so this system should be flying soon! :p pic doesn’t show it, but I ordered parity ram.

Sphere478 wrote on 2023-01-07, 03:24:

Today I got some 16mb sticks in the mail. 4 of them […]
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Today I got some 16mb sticks in the mail. 4 of them

They unfortunately don’t seem to be supported.

I got parity ones. Could that be it? Or are they simply just not supported?

4mb x 8 it is then?

From the information I could find, which was quite scant, it looks like the board supports 256Kx8, 1Mx8 and 4Mx8 Simms. So unfortunately the board tops out at 32MB. But for a 386DX-40 that's pretty nice for me. I am still dealing with some weird quirks, but I think they are caused by what I am doing. The Sound card mixer thing doesn't just affect the Aztech card. It actually effects 2 of my Sound Blaster cards as well. Namely a CT22-- something Vibra16 and the Sound Blaster 16 with all of the different drive interfaces on it. I have never encountered it before, so it's strange, but trying out the cards in other machines, 486, and pentium the mixer issue persists with the cards. So it's not system specific.

Have you tried using UNISOUND to set your volume? It should be able to set it across pretty much all of your sound cards. Not sure if it would make a difference, but it's worth a try - at the very least it's a nice all-in-one sound config utility that works with the majority of DOS sound cards.

megatron-uk wrote on 2023-01-17, 10:59:

Have you tried using UNISOUND to set your volume? It should be able to set it across pretty much all of your sound cards. Not sure if it would make a difference, but it's worth a try - at the very least it's a nice all-in-one sound config utility that works with the majority of DOS sound cards.

I did try that. It still resets with the games. It has to be something hardware related

I was able to upgrade the motherboard to the apparent max supported memory of 32mb with parity. Using 9 chip sticks. 3 chip sticks won’t work unfortunately 🙁

I get a parity error (unsurprisingly) when mixing 8 and 9 chip sticks. Didn’t test if (only) 8 chip sticks work, but they may if only 8 chip sticks are present.

I was also able to get scsi and gotek working on this motherboard and loaded up windows 95c and it seems to work pretty well with the 32mb now.

I think I’ll probably get one of the pi blue scsi adapters. Next to get the seek milliseconds down and speed it up there also.

Last step will be to put in the sxl2 and interposer, then it should be the fastest version of its self. Unless anyone has more upgrade suggestions.

This sounds super exciting! I can't wait to see the numbers when you are done!

16mb 30pin modules are rarely supported on 386, the most you can get is 4MB modules for 30 pin slots for 386, early ones will only support 256K and 1MB modules. Late 486 yes sure.

Cheers,

None of my 486 motherboards that use 30 pin modules support 16MB modules. Granted most of them are from 1991-93 or so. All off my later 486 boards are PCI and they use 72 pin memory modules instead. Are there specific boards that I can put an eye out for? I would be really interested in using one of them.

Any thought as to wether there is a jumper on this motherboard for putting the onboard cpu into flt? So as to allow the socketed cpu to function?

386—>486 build

I’m basing a build on this mobo now.

Btw, I disabled the onboard cpu by lifting flt pin and pulling flt to gnd.